1. Field of the Invention
The invention relates to implantable hearing assistance devices and components thereof.
2. Description of Related Art
The field of implantable hearing assistance systems presents many challenges, not the least of which is the small physical size of some implantation regions. It is desirable to make the components of any implantable hearing assistance system as small as possible to fit into the limited space of the implantation area, yet adaptable to allow for the various surgical and natural morphological differences found at the site of implantation.
In some types of implantable hearing aid systems, transducers located within the middle ear engage one or more auditory elements and transduce mechanical vibrations into electrical signals and vice versa. Typically, electrical signals are amplified and transmitted to an electromechanical output transducer, which in turn vibrates a bone in the ossicular chain of the middle ear by translating the amplified electrical signal. It is typical for the amplifiers and other components of the system be located away from the middle ear. These other components might include: batteries, filters, compression devices, microphones, and other components. These components can be located in the skull, mastoid, chest area or other locations. Electrical communication must take place between the transducers and other components located in the middle ear or the inner ear region, and those located elsewhere. During the implantation procedure, it is typical to implant the components within the middle or inner ear before electric communication is made with the other necessary components of a hearing assistance system. Once the middle or inner ear components of the hearing assistance system have been implanted, and the other components of the system are implanted or ready for use, the battery and other electronics located away from the middle ear are typically connected with the transducers and other components of the middle ear. It is not atypical for the middle ear components of an implantable hearing assistance system to join at an electrical connection with those components located away from the middle ear components. It is vital to the operation of the hearing assistance device that a reliable electrical connection be made.
In cases where the electrical connection must be made within the body, or very close to the area of surgical intrusion, fluids will likely be present. These fluids can become problematic when attempting to connect the components of the system. Problematic fluids might consist of bodily fluids or fluids introduced during the implantation surgery, such as sterile saline or other irrigating fluids used to flush the implantation area. When these fluids are present in the region of the electrical connection, the fluids may inhibit electrical communication. Further, where a plug-type connector is used, it may be difficult to engage the two members of the connector if fluids exist in the cavity of the connector. Even if no, or only a small amount of fluid is present, a plug-type connector with an effective seal may create a high pressure area inside the connector, as the connector members are coupled. If other restraining measures are not taken, the leads of the connector may back out under the pressure created inside the connector, disrupting electrical communication.
It is therefore an object of this invention to provide a connector that can be made small, that has effective sealing and restraining properties, and from which unwanted fluids and pressure can be vented.